Electrical issues

Hey,
I'm new to the forum so bear with me please! I recently replaced the clutch position switch and ignition switch on my 02' Hyundai Elantra GT. When I put everything back together I found that several of my electronics (which previously work fine) no longer work, such as my gas gauge shows random readings and the gas light comes on and off periodically regardless of how much fuel is in the car, the interior lights won't come on anymore, the stereo is out, the dash board clock, and the electronic door locks don't work unless the key is in the on position. Before you ask, yes, I checked every fuse in my car, both under the steering wheel and out in the fuse relay box out by the battery. I checked the back of my stereo with my volt meter and found that it WAS getting power through the red wire, but the yellow(accessory) wire was not getting anything at all... Any thoughts or suggestions would be greatly appreciated. I just really don't want to tear my entire car apart trying to find where this is coming from. Thanks in advance!